Australia and New Zealand's food regulator is failing to apply its own safety standards, or those of international guidelines, in assessing a new-generation GM corn for human consumption, critics say.

But Food Standards Australia New Zealand (FSANZ) defends its so-far favourable assessment of the high-lysine corn, which it says is intended for animal feed and is unlikely to enter the human food chain.

"Among the types of potential hazards that this food poses are the creation of compounds that are known to be associated with important diseases like diabetes, Alzheimer's, heart disease and cancer," says centre director Associate Professor Jack Heinemann.

Heinemann says while the compounds, advanced glycoxidation endproducts (AGEs), are also produced when cooking conventional foods, he is concerned about potential levels in LY038 corn.

He says corn is normally extremely low in the compounds that combine to create AGEs.

But he says higher-than-normal levels of lysine in the LY038 and high sugar levels, combining under heat, have the potential to raise AGE levels.

"[LY038] has the potential to produce 100 times more [AGEs] than normal corn," says Heinemann.

Draft approval by FSANZ

In March this year FSANZ recommended LY038 be approved as safe for human consumption in a report to its board.

"Food derived from corn line LY038 is as safe and wholesome as food derived from other corn varieties," the report says.

But the necessary tests to prove the corn is safe for humans have not been done, says Heinemann, a geneticist and former US National Institutes of Health scientist.

He says LY038 is the first of a new-generation of GM foods being specifically designed to be nutritionally different from their conventional counterpart. And FSANZ's decision could set a precedent on how such foods are assessed.

Tests of cooked corn?

Heinemann says FSANZ only considered safety tests that looked at raw and not cooked corn.

But the international standards-setting body Codex Alimentarius recommends heating, cooking and processing conditions be applied to GM material in an assessment of their safety for human food, says Heinemann.

He also says FSANZ only considered 21-day animal studies and not longer ones, which might have picked up diseases like cancer. Heinemann says FSANZ should also look into human feeding studies.

Lastly, Heinemann criticises FSANZ's decision to compare the composition of the corn to another GM corn rather than its non-GM parent variety, as recommended by its own advice, and by Codex.

Safety assessment defended

FSANZ says testing was adequate.

"We are satisfied that we have all the scientific information necessary to make a sound decision on the safety and nutritional adequacy of high lysine corn LY308," it says.

"We have considered the potential for production of AGEs, but have no concerns."

FSANZ says Codex only asks regulators to consider testing heated or processed GM foods. But as the raw corn has much lower levels of lysine compared to other foods regularly consumed, FSANZ did not consider the tests necessary.

It also says the GM corn used for comparison was a "better comparator than the non-GM parental line".

FSANZ says it assessed the corn as if it was any other GM food.

"The safety assessment conducted on LY038 is as rigorous and thorough as for any GM food product, and assumes that if approved, corn from line LY038 could be routinely entering the food supply and not present just as an occasional inadvertent ingredient," states FSANZ's report.

Will it enter the human food supply?

FSANZ also says the corn is "unlikely" to end up in human food and is only being assessed as a precaution in case of an accidental mix-up.

One such mix-up occurred in 2000, when Starlink GM corn, also intended for animal feed, became mixed in the US food chain.

Because it was not registered for human consumption the contamination affected exports and cost the manufacturer a $100 million in lost sales.